PubMed HealthSearch

Biomedical subjects

E Leicht

Publications and source records attributed to E Leicht.

11 recordsLinked to original sources

[Sphincter-preserving radiotherapy of anal carcinoma].

During the last decade radiotherapy, in combination with chemotherapy, has become the treatment of choice in cure of anal carcinoma with preservation of anal function, and has replaced abdominoperineal resection (APR). From 1979-1990 54 patients with anal carcinoma were treated by radiotherapy. 24 patients received radiotherapy after APR (12 adjuvant, 12 after recurrence). 11 received palliative radiotherapy without prior APR. 19 patients were treated curatively, 17 of whom received a combination of external irradiation followed by interstitial iridium implantation in a split course regimen. 11 of the 19 patients received short simultaneous chemotherapy (mitomycin C and 5-fluorouracil). All 19 patients had a complete remission. 18/19 patients had no local recurrence after mean 14 months' follow-up. 2 patients developed regional recurrence. 3 patients died of other causes. Colostomy was necessary in 5/19 patients with anal necrosis which was dose-related. The maximum tolerated dose was 71.4 Gy. Our results support the recommendation in the literature of primary, curative, radiotherapy and chemotherapy of anal carcinoma with preservation of the anal sphincter.

Adult

[Cardiac function and the skin microcirculation in acromegaly].

The microcirculation was measured by nail-fold capillary video microscopy in 21 patients (12 men, 9 women; mean age 54.7 [29-74] years) with acromegaly. Levels of growth hormone (12.0-71.7 microU/ml) and of somatomedin C (2.4-10.5 IU/ml) were elevated in 10 patients, despite preceding treatment. Eleven patients had an increase in myocardial thickness and nine had impairment of left ventricular function, although only slight in most. Left ventricular hypertrophy was demonstrable even in the absence of hypertension. No patient had evidence of coronary heart disease. Nail-fold capillary video microscopy (capillary density, torque index, reactive hyperaemia, epidermal blood flow) failed to distinguish between successfully treated patients and those with persistently elevated growth hormone concentrations or disease duration of over 5 years. There was no evidence of inadequate capillary blood flow as a cause of abnormal function in hypertrophied organs.

Acromegaly

Hypomagnesaemia-induced hypocalcaemia: concentrations of parathyroid hormone, prolactin and 1,25-dihydroxyvitamin D during magnesium replenishment.

Three patients with hypomagnesaemia-induced hypocalcaemia were investigated during the phase of magnesium replenishment. Before treatment, serum levels of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were at the lower limit of normal. In spite of a rapid rise of parathyroid hormone (PTH) after intravenous administration of magnesium, a reactive increase in 1,25-dihydroxyvitamin D in serum was absent or delayed. The increase of serum calcium into the normal range occurred before any consistent change in the concentrations of this vitamin D metabolite. The rise of serum prolactin in response to the increase in PTH was blunted or absent, and is a further example of a transient PTH resistance during the phase of magnesium replenishment.

Alcoholism

Mechanisms of hypocalcaemia in the clinical form of severe magnesium deficit in the human.

Severe magnesium depletion leading to hypocalcaemia has been described in a variety of clinical settings. Inadequately low concentrations of parathyroid hormone (PTH) are a constant feature of hypomagnesaemic hypocalcaemia (HMHC), while target organ resistance to PHT in kidneys and bone may be demonstrated in the majority of these patients. The failure of membrane-bound adenylate cyclase in the parathyroids, kidneys and bone, thought to be the most important molecular mechanism in HMHC, cannot explain the concomitant resistance to vitamin D and its metabolites. In recent years, information has accumulated on further magnesium-dependent intracellular events and alternative pathways of transcellular signalling. This may eventually allow the identification of one or more further biochemical mechanisms leading to hypocalcaemia in severe magnesium deficiency.

Adenylyl Cyclases

Tumoral calcinosis: accumulation of bone-seeking tracers in the calcium deposits.

Rapid and preferential uptake of 47 calcium 87m Strontium by the multinodular calcareous masses was seen in a patient with tumoral calcinosis. Using 87m Strontium, scintigraphic imaging of the tumors was achieved, while the skeleton was barely visible. More intense accumulation of 87m Sr. in one tumor suggested a higher rate of calcium depostion. This was in agreement with the observation that this tumor showed less tendency to decrease in size during calcium and phosphorus deprivation therapy. Quantitative measurements of the uptake of bone seeking tracers by the tumors may be of value in estimating calcium turnover in the calcified masses.

Calcinosis

Phosphonopeptides as antibacterial agents: metabolism and pharmacokinetics of alafosfalin in animals and humans.

The metabolism and pharmacokinetics of a synthetic antibacterial phosphonodipeptide, alafosfalin, have been studied in rats, baboons, and human volunteers. The compound was rapidly absorbed from the injection site after subcutaneous and intramuscular administration and gave peak plasma concentrations at 15 to 20 min after dosing. Distribution studies showed that high drug concentrations were produced in inflammatory exudates and most tissues except brain. Alafosfalin was rapidly cleared from the general circulation, mainly by the kidney. Plasma half-lives were 20 min in rats and approximately 1 h in baboons and humans. Alafosfalin was well absorbed after oral administration, but was extensively hydrolyzed to alanine and L-1-aminoethylphosphonic acid before it reached the general circulation. This first-pass metabolism was less marked in humans than in animals. Administration of 200-mg intramuscular and 500-mg oral doses produced concentrations of intact phosphonodipeptide in human plasma and urine which were in excess of the in vitro minimal inhibitory concentrations for many pathogenic organisms. The rate of absorption and elimination of alafosfalin in humans were also very similar to published data on beta-lactam antibiotics. This suggests that the pharmacokinetics can be matched to provide synergistic combinations for clinical use.

Alanine

[Hyperthyroidism with hypercalcaemia (author's transl)].

Anorexia, constipation, vomiting and somnolence in a 39-year-old woman were at first misinterpreted as being of psychological and autonomic nervous system origin. Further clinical and biochemical tests revealed hyperthyroidism associated with hypercalcaemia and hypercalciuria. Thyrostatic treatment for 12 days caused regression of the hypercalcaemia and, after subtotal resection, serum calcium levels and urinary calcium excretion returned to normal for good. The hypercalcaemia syndrome must therefore be assumed to have been the direct result of the hyperthyroidism.

Adult